Control means for burners



A ril 30, 1940. T. A. WET Z EL 2.198.895

CONTROL MEANS E759 BURNERS Filed Feb. 1, 1937 2 Sheets-Sheet 1 5m M w jazz/Ma April 30, 1940. w L 2,198,895

CONTROL MEANS FOR BURNERS Filed Feb. 1, 1937 2 Sheets-Sheet 2 Patented Apr. 30, 1940 UNITED STATES; PATENT OFFICE 2,198,895 CONTROL MEANS FOR BURNERS Theodore A. Wetzel, Milwaukee, Wis.,asslgnor to Milwaukee Gas Specialty Company, Milwaukee, Wis., a corporation of Wisconsin Application February 1, 1937, Serial No. 123,361

21 Claims. (Cl. 236-1) burner employed in the oven, a thermo-electric safety shut-off device for shutting off the supply of fuel to the main burner whenever the pilot burner is extinguished. In connection with this feature, I provide a structure wherein the main supply valve tends to return to closed position when manually opened, until such time as the pilot burner is again ignited.

Another object of the present invention is to provide, in addition to the shut-oil? means controlled by the pilot burner, an oven heat regulator and thermostat for maintaining selected temperatures in the oven by control of the gas flow to the main burner. In conjunction, with the means for selecting the desired temperature in the oven I provide remotely operating reset means for opening the pilot burner supply valve and the main burner control valve to secure ignition of the pilot burner and consequent ignition of the main burner.

In the preferred form of the invention I contemplate providing a main control unit, disposed between the gas supply manifold and the burner pilot burner.

Incorporated in the same unit is a secondary controlvalve for regulating the flow of gas to the main burner in accordance with'the temperature which it is desired to maintain in the oven or other medium to which heat is supplied by this burner. This valve is under the conjoint control of a thermostat disposed in the space being heated and responsive to temperatures therein,

and a selecting device mounted remote from the unit and the oven for determining or selecting the desired temperature. The selecting device also includes means for resetting the cooperating pilot and main burner valves when it is desired to ignite the pilot burner.

This

Another feature of the present invention residesin the construction and arrangement of the constituent parts of the control unit, and their interconnection and disposition for facilitating control thereof by the various remotely disposed controlling members, such as the thermocouple, thermostat and selecting and resetting device.

Still another advantage provided by the present invention resides in the improved control unit with its compact and simplified arrangement. of

parts, and improved means for controlling the burner fuel supply and the valve resetting mechanism.

Other objects and advantages of the present invention will appear more fully from the following detailed description which, taken in conjunction with the accompanying drawings, will disclose to those skilled in the art the particular construction and operation of a preferred form of the present invention.

In the drawings:

Figure 1 is a front elevational view, with parts thereof broken away, showing a preferred manner of arranging the control unit and actuating devices of the present invention as applied to a cooking range; 1

Figure 2 is a transverse sectional view, being more or less of a developed sectional view taken substantially on line 22 of Figure 1; and

Figure 3 is a sectional view taken through the selecting unit shown in Figure 1.

Referring now in detail to the drawings, I have shown in Figure 1 a kitchen range or the like indicated generally by the reference numeral 5, having a flat top 6 within which are disposed open top range burners, provided with the front panel member 1 upon which is mounted the control cocks for the burners and behind which extends the fuel supply manifold 8 having a pilot burner supply I3 connected thereto and having a valve il-therein controlled by the gas cock 10 for supplying fuel through the member l2 to the main oven burner supply conduit- H.

The range oven is indicated generally at l5, having the usual horizontally hinged door H5 at the front thereof, and (comprising a pair of spaced wall members l1 and I8 between which may be disposed insulating material as indicated at l9.

Below the oven compartment I6 is disposed the main burner indicated generally at 20, this burner being provided with a flange portion 22 adapted to engage about the defining edge of an opening 23 formed in the side wall of the range, and having the air inlet portion 24 into which the gas spud 25 is adapted to extend.

Disposed in the upper portion of the oven [5 is a pressure type thermostat 26, which may comprise a bulb or other type of containing member having the relatively small conduit 21 extending therefrom to the control unit indicated generally at 28. The tube or conduit 21 is preferably capillary in size, so that slight changes in pressure within the bulb 26 will be transmitted practically instantaneously to the pressure actuated means within the control unit 28.

Mounted upon the front panel 1 of the range is a suitable selecting mechanism indicated general-- ly at 29, anddisclosed in detail in Figure 3. The member 29 is provided with a conduit 38 leading therefrom behind the panel 1 and behind. the front wall 32 of the range downwardly to the control unit positioned adjacent the main oven burner '28. I The purpose of this conduit will be described in detail in connection with the description of the control unit.

Considering now in detail the structure shown in Figure 2, the control unit comprises a housing 35, having the threaded extending bosses 36 and 31' projecting from one side thereof, these bosses being adapted to receive the lower ends of the pilot gas supply conduit 13 and the main oven burner gas supply conduit l4, these conduits being secured within the bosses 36 and 31 by the cap nuts 38 and 38, respectively, in a manner which is well known.

The pilot burner conduit l3 opens into the chamber 48' formed in the housing 35, the chamber 48 in turn opening into the inlet chamber 42 of the pilot burner control valve assembly through the port 43, this port being controlled by a metering screw 44 to predetermine the quantity of fuel being supplied to the pilot burner.

The outlet chamber 45 of the pilot valve assemblies communicates with the inlet chamber 42 through the valve passage 46, and from the chamber 45 a suitable conduit connection 41 is provided leading to the pilot burner 48. The pilot tip is supported by threaded engagement upon a fitting 48 which, in turn, is supported by suitable means below the oven burner 28, as illustrated in Figure 1. The pilot tip 48 preferably has open- I ing means along the bottom and inner end, at

which opening means the pilot-flame burns as indicated at 50 in proximity to the oven burner 20. The particular form of the pilot tip and the particular arrangement of the opening therein for producing the pilot flame may, of course, vary widely within the scope of the present invention. The main fuel supply conduit l4 opens into the chamber 52 formed in the housing 35, and the fuel from this chamber passes through the valve opening 53 into the chamber 54, andthence outwardly through the passage 55 into the chamber 56, which has a laterally extending boss 51 providing a connection for the nipple 58 through which the gas is supplied to the spud 25 for entrance into the bell 24 of the main oven burner. It will be noted that the spud 25is adjustably threaded upon the end of the nipple 58, the nipple in turn being provided with a projecting stud portion 58, whereby the amount of gas flowing outwardly through the port 68 of the spud may be controlled. I I

Preferably a suitable by-pass opening 82 is provided between the chambers 54 and 56, controlled by the metering screw 63, so that in the event valve passage 55 is closed, a sumcient amount of gas will still flow to the burner to maintain a minimum quantity of gas thereto to insure continuous ignition of the oven burner. I

Considering now in detail the thermal electric cutoff for controlling the supply of fuel to the extending substantially coaxial of the passageways 46 and 53. A suitable bushing 85 is mountalso provided with the axially extending counterbored portion 18 adapted to receive the inner end of a spindle member 12 extending outwardly from the recess 68. The member 12 is provided with a collar 13 intermediate its ends, this collar serving to form a seat for one end of the spring 14; the opposite end of the spring 14 being biased against the inner face of the recessed portion 88 of the member 88. The end of the member 88 is spun over, as at 88', to form a stop for the spindle collar 13. It will thus be noted that the spindle member 12 is capable of relative movement with respect to the member 68, with the spring mem ber 14 normally urging the spindle 12 outwardly with respect to the recess 68. Adjacent its inner end, the member 68 is provided with a reduced portion 15 formed with a conical surface 16 at the end thereof adapted to form a valve seating portion engaging the defining edge of the passageway within the bushing 65. I

The opposite end of the spindle 12has abutting engagement with a valve member indicated generally at 11 adapted to engage the valve seat 18 formed at the inlet side of the passageway 53. The valve member 11 is provided with a valve disc retaining portion 18 having a socket therein adapted to receive the ball end of a valve stem member 82. Secured about the socket por- .tion 18 is a cup-shaped member 83 which is fixed for conjoint movement with the valve '11, and which forms an enclosing retainer for the relatively heavy spring 84. The spring 84 is biased at one end against the interior surface of the base of the cupshaped member 83, and at its opposite end bears against a washer engaging suitable packing 86 disposed between the washer and the outer surface of the base of a second cup-shaped member 81. The member 81 is thereby fixed in position within the recess of the, housing 35, and is sealed against passage of gas therepast by the gasket member 86. The outer end of the valve stem 82 is provided with a reduced portion 88, adapted to receive an armature member 88, this armature member being loosely secured to the valve stem 82 by means of the nut '80 engaging the projecting threaded end of the valve stem. This swivelly mounts the armature disc 88 in position with respect to the valve stem 82, and assures that it will have free movement within the cup-shaped member 81, being centered upon the valve stem in such manner that it will also be centered within the member 81 so as to be normally disposed out of contact with the inner surfaces of the cylindrical wall thereof.

A suitable magnet frame 82, which is formed of an annular member having a double wall within which is disposed the electromagnetic coil 83, has the end surfaces thereof formed for engagement by the armature 88 when the magnet 82 is energized. One end of the coil 83 is connected to the threaded cap member 84 which threads into I an enlarged end 85 of the housing 35, and which has internal shoulder portions engaging the external shoulders of the magnet in order to lock the same in fixed position within the housin'g, A suitablegasket 98 may be interposed between the inner end of the member and the inner end of the-enlarged recess 95.

The opposite end ofthe coil 93 is connected through conductor 91 with a conductor 98 carried within'suitableinsulating means disposed within the interior'of a metallic tubular member I88 that extends into the end of the cap member 94. The tubular member I88 forms one conductor for a thermocouple circuit which includes the conductor 98 as the other line conductor.

- Thus the coil 93 is connected between the conand at its opposite end is provided with a productors 98 and I88, and current flowing through these conductors will energize the coil 93. The conductor or tube I88, with the' inner conductor 98 therein, extends substantially along the line ofthepilot burner supply conduitv 41 to the fitting 49, and-is clamped in this fitting so that the extremity thereof, which is formed of dissimilar metals to provide a welded junction I82 forming the hot junction of the thermocouple produced thereby, is disposed in the path of the pilot burner flame 58. -It will thus be seen that the junction I82 has one conductor extending therefrom in the form of the outer enclosing metallic tube I 88 connected through the cap member 94. to one end of the coil 93, and the opposite conductor I thereof is enclosed in insulated relation within the metallic tube I88 and is connected at its opposite end to the other terminal of the coil 93 through the conductor 91.

The housing 35 is provided, adjacent the pilot valve member 68, with an offset internal extension I85, adapted to form a suitable guiding support for a spindle member I86 which, at its inner end, is adapted to have abutting engagement with the valve end portion 15 of the member 58,

jecting fin portion I81 having rocking engage ment within the cross arm or lever I88. A suitv able spring I89 is biased between. a thrust collar II8 carried on the extending end of the spindle I88 and a packing washer II2 adapted to compress suitable packing I I3 into position about the lateral surface of the spindle I86 in order to prevent passage of gas from the pilot supply outlet chamber through the spindle passageway I85.

The end of the housing 35 is provided with a thickened shoulder "4, which is adapted to be closed by a suitable cap member II5 secured to the shoulder II4 by means of a plurality of cap screws Hi, there preferably being a gasket II1 interposed therebetween for sealing the interior of the chamber.

. The cap member II5 is-provided with a suitable offset cylindrical portion II 8, which is provided with an extending boss I I9 to which is sealed the conduit 38, as by means of solder indicated at I28, or the like. Disposed within the interior of the chamber II8 isa bellows-like pressure-actuated member I22, which is provided at its inner end with a flange portion I23 sealed to a suitable shoulder formed in the inner surface of the cap member II5, as indicated at I24. Extending through the bellows member I22, and secured to a bimetallic end closure I24 thereof which compensates for temperature changes, is a plunger member I25 projecting into unit 35 and having the pin-like projecting portion I26 pilotedin the cross-arm or lever I88. It will thus be apparent m is filled with a suitable liquid which is not through the capillary tube 33 with the interior of the chamber I28 formed at the selecting means 29, as shown in Figure 3. Chamber I28 is formed as a substantially cylindrical cup-shaped stamping, provided with a shoulder portion I29 adapted to receive one end I38 of a suitable bellows member I32 sealed annularly at the shoulder I29 and carrying a closed end portion I33 at its opposite end, which is maintained in abutt engagement with a threaded spindle I34. The base end of chamber I 28 is provided with a bimetallic disc I28 to correct the pressure due to temperature changes.

The spindle I34 is adapted to be threaded through a suitable bushing member I35 carried be painted thereupon, as desired. The spindle I34. is provided with a reduced-portion I38, to which is secured a dial or indicating member I39, the same being clamped to' the spindle by the nut I48. By registering suitable indications upon the annular surface of the'dial member I39 with the indicator I31, the spindle is adjustably threaded within the bushing I35, to produce a corresponding expansion or contraction of the bellows member I32. The chamber I28 being filled about the external surface of the bellows with the liquid which communicates with the liquid in the chamber II8, it is apparent that upon expansion of the bellows I32 in the chamber I28, a pressure will be transmitted to the liquid in the chamber II8, collapsing this bellows to the same extent, and thereby producing an outward thrust on the spindle I25, thus causing bearing member I42 carried by the arm I88 to be moved to the left. we

Similarly, a collapse of the be lows I32 within the chamber I28 will reduce the pressure in this chamber, and consequently reduce the pressure in the chamber I I8, thereby causing an extension of the bellows I22 and a retraction of the spindle I25 with respect to the arm I88.

Considering now in detail the oven heat regulating mechanism, the selecting member 29, with the component parts as illustrated, is connected to the cross-arm I88 with a suitable bearing member I42 adapted to have bearing engagement against a spring follower member I43 receiving one end of a coil spring I44. The opposite end of the spring I44 is engaged in the spring follower I45, which, in turn, is supported for bearing engagement about the pointed end of a valve stem member I46 connected to a 'valve member I41 carried by a suitable Sylphon'bellows or similar pressure-actuated member I48. which is sealed to the inner end of a threaded cap member I49, as indicated at I58. The cap member I49 is provided with a suitable passage at its outer end into which extends the conduit 21, the conduit being sealed thereto as i'ndicated at I52. The interior of the bellows I48, the cap member I49, the tube 21, and the bulb 26 in the oven chamber are filled with a vapor-liquid medium producing pressure variations in accordance with temperature variations at the bulb 26.

Variations of temperature in the oven will result in variations in pressure within the bulb 25, producing a transmission of this pressure'through the tube 21 to the interior of the bellows member I48, thereby producing a variation in the podtloning of the valve I 41 with respect to the passage 55.

In order to produce an initial setting of the valve member I41, the selecting spindle I84 is. rotated to an extent determined by the indicato put a predetermined tension upon the spring.

I44, which transmits this tension through the spindle I46 to the valve member I41, thereby producing a predetermined pressure within the bellows I48 and within the bulb 20. This initially positions the valve member for operation to produce a predetermined temperature within the oven, the mechanism being calibrated to provide the desired effect. However, as the temperature in the oven builds up, expansion of the fluid in the bulb 26 will result in expansion of the bellows I48, slightly closing the valve member I41, and thereby reducing the flow of gas to the burner 20. Similarly, a decrease in temperature within the oven below that required will result in collapse of thebellows I48, opening the valve I41 and providing for an increasedfiow of fuel through the passageway 55 into the chamber 56 and thence to the burner 20.

Assuming now that the parts are in the position shown in Figure ,2, with the burner and the pilot burner 48 ignited, and the selecting mechanism set to provide a predetermined temperature within the oven, variations from this temperature will produce variations in the position of the bellows I48, thereby controlling within a limited range the amount of variation of temperature within the oven with respect to the selected temperature. These variations, due to expansion and contraction of the fluid in the bulb 28, will be resisted by the pressure of the spring I44 and will maintain the temperature within the oven at approximately the desired temperature. Although spring I44 tends to rock the arm I08 about the pin portion I28 of the spindle I25, such movement is not possible due to excessive pressure of spring I09. Assume now that the pilot bumer becomes extinguished, due

to a draft, or for any other reason. The thermocouple element of junction I02 immediately cools, thereby deenergizing the coil 93 and thus deenergizing the magnet frame 92. As a result, the armature 89 is. no longer held against the base 01' the magnet 92, and the spring 84, which is a relatively powerful spring, urges the valve member 11 down onto its seat I8. Upon initial movement of the valve member 11 towards its seat,

the spindle member 12 is moved inwardly, and, due to the pressure of the spring 14, tends to compress the spring, 68, thereby moving the member 68 inwardly with respect to the valve seat 65, and moving the pilot valve control member into valve-closing position. Any amount of lost motion required, due to differences of positionof the valve members TI and I6 with respect to their respective seats, will be accommodated by the sliding movement of the spindle 12 with respect to the recess I0, under the influence of spring I4, so that as the pilot valve member I6.

seats prior to seating of the valve 11, the spindle I2 has suflicient lost motion movement to allow seating of the valve II. In the preferred construction the spring 14 allows valve I6 to seat slightly sooner than valve 11, and accommodates ly, the plunger end saucepan the necessary wertravel to provide for positive seating 01 both members.

It should be noted that the valves are seated without rocking arm I 08 about the pin portion I20 of the spindle I25. With the valves thus closed, the fuel supplied to both the pilot burner and the main burner is shut 01!, and consequently no i'uel escapes. the pilot burner, in order to allow ignition of the main burner, the reset stem I80, carried'within the spindle I84 and projecting outwardly from the selecting means 29, is pushed inwardly man- -I62 th'ereot engaging the end I38 of the bellows I32 to expand the same, thereby increasing the pressure of the fluid in the chamber I28 to an extent such as to collapse the bellows I22 and force the spindle I25 outwardly of the bellows, thereby placing pressure upon the cross-arm I08. As a result, the crossarm I 08 tends to move to the left, and by reason of the stop member I64 provided in the housing 35, if the cross-arm I08 tends to pivot in a clockwise direction about the spindle I25 due to the strong pressure of spring 84 and I09, the stop member prevents such movement and insures that the cross-arm I08 will impart a translatory movement to the spindle I06 suflicient to move the valve member I6 and the valve member I! away from, the valve seats and to compress the spring 84, whereby the armature 89 is moved into engagement with the magnet face of magnet 92. This allows gas tov flow to the pilot burner, whence it is ignited and the heat thereof applied to the'thermocouple. As soon as the thermocouple junction I02 becomes heated, the magnet coil 93 is energized, and consequently maintains the armature 89 in attracted position against the magnet frame. The reset stem I can then be released, and the parts assume normal operating position.

It is to be understood, of course, that the temperature desired within the oven can be controlled by the selecting means independently of the operation of the control valves actuated by and under the control of the thermocouple. The metering passageway 62 is provided to insure a minimum flow of gas to the main burner 20 even when the valve I4! is closed over the passageway 55, this minimum How to the burner being found: desirable in some instances.

I am aware that various changes may be made in details of the constituent parts of the present invention, and in their arrangement and coopcrating relationship with respect to other of the parts thereof, and I do not intend to for closing both said valves, secondary valvev means in said unit for controlling flow of fuel to said main burner, means acting in opposite directions on said secondary valve means for selecting and maintaining a predetermined operating temperature at said main burner, a thermo- When it is desired to reignite i couple subject to the heat 1' the pilot burner, an 15 resetting said armature to attracted position and said main burner valve to open position.

2. The combination, with a pilot burner and a main burner having separate fuel supply conduits,

' said burners, including normally' closed shutsaid main burner being adapted to supply heat to an enclosure, of a common control unit for both of! valves insaid conduits, means responsive to ignition of the pilot burner, for holding said valves open but inoperative to move said valves to open position, a secondary valve in said unit for said main burner, remotely disposed selecting means acting to control the position of said secondary valve for maintaining a predetermined temperature in said enclosure, and means actuated by a portion of said selecting means for resetting the means for holding the valves open.

3. In combination, a control unit having separate inlet. passages for receiving fuel for a main burner and a pilot burner, valves in said passages having limited lost motion connection therebetween and normally conjointly urged toward closed position, thermo-electric means responsive to ignition of said pilot burner for holding said valves open, outlet passages in said unit for each of said burners, a secondary valve in thefoutlet passage for the main burner, pressure-actuated selecting means operable from a remote point for selecting the position of said secondary valve, opposing pressure-actuated means responsive to the. temperature developed by said main burner for controlling said valve position, and means actuated by a portion of said selecting means for resetting the thermoelectric means for holding the valves open.

4. A control unit adapted to be interposed in the fuel supply lines between a gas supply manifold and a main burner and associated pilot burner, comprising a housing having separate fuel supply inlets'and outlets for each of said burners, a pair of valves between the inlet. and outlet for the main burner, a single valve between the inlet and outlet for the pilot burner, remotely'disposed selecting means for controlling the operating position of one of the main burner valves. remotely disposed means for varying said position in accordance with temperature variations produced by said main burner, means interconnecting the other main burner valve and pilot burner valve for conjoint operation, theremoelectric means for holding one of said last two valves open when said pilot burner is ignited, means for closing said valves upon extinguishment of said pilot burner, and resetting means for said last two valves" actuated by a portion of said selecting means.-

5. In combination, a fuel supply manifold, a main gas burner, an associated pilot burner, fuel supply conduits between said manifold and each ofsaid burners, a control unit having valve means controlling gas flow through both conduits, thermoelectric means for holding the valve means for one conduit open when the pilot burner is ignited, means for shutting off the valve means for both said conduits upon extinguishment of said pilot burner, a second valve in said unit for controlling the main burner conduit, pressure actuated means in said unit operable by a remotely disposed pressure developing means for selecting the operating position of said valve, opposing pressure actuated means insaid unit for varying the said position in accordance with remotely'disposed pressure means responsive to temperatures developed by said main burner, and means actuated by a portion of said selecting means for resetting said. thermoelectric means.

6. In combination, a fuel supply manifold, a main gas'burner, an associated pilot burner, fuel supply conduits between said manifold and each of said burners, a control unit having valve means controlling gas flow through both conduits, thermoelectric means for holding-the valve means for one conduit open when the pilot burner is ignited, means for shutting off the valve means for both said conduits upon extinguishment of said pilot burner, a second valve in said unit for controlling the main burner conduit, pressure actuated means in said unit operable by a remotely disposed pressure developing means for selecting the operatingpositi'on of said valve, opposing pressure actuated means in said unit for varying the said position in accordance with remotely disposed pressure means responsive to temperatures developed by said main burner,

and reset means disposed at said selecting means and independently-operable through said first pressure actuated means in said unit for resetting said valve means.

'7. A control unithaving separate passages therethrough for supplying fuel to a main burner and to an associated pilot burner, valve means in said unit controlling said passages, thermoelectric means responsive to ignition of said pilot burner and including an electromagnetic coil in said unit for normally holding the valve means for one of said passages open, spring means for closing the valve means for both of said passages upon extinguishment of .said pilot burner, a main burner control valve in the main burner fuel supply passage in said unit, bellows means connected to said valve at one end of said unit and to a remotely disposed pressure developing member responsive to the heat of said main burner, a second bellows in the opposite end of said unit and carrying an inwardly projecting spindle, a cross-arm on said spindle, remotely disposed selecting means including a pressure developing member for actuating said second bellows to produce predetermined movement of said cross-arm, resilient means actuated by said cross-arm for prestressing said first bellows means to eifect a predetermined operating position of said main burner control valve, means at said selecting means and operable independently thereof for actuating said cross-arm, and motion-transmitting means between said crossarm and said valve means for resetting said valve means.

8. In a system of the class described wherein there is a main burner, a pilot, burner, fuel supply means for the main burner and said pilot burner, controlling means including a main burner valve operative to control the fuel supply for the main burner and a pilot burner valve for controlling the fuel supply for the pilot burner, the combination with said system of a thermocouple subject to the heat of the pilot burner, an armature connected to the main burner valve, an electromagnet connected to said thermocouple and cooperable with said armature to hold said main burner valve open by ,energization of the electromagnet by the thermo-electric current set up by said thermocouple when the pilot burner-isignited, means for moving said main burner valve and said pilot burner valve to closed position upon extinguishment 01' said pilot burner, selecting means for setting said controlling means for maintaining different temperatures, and resetting means actuated by a-portion of said selecting means and common to said main burner valve and said pilot burner valve for moving both said valves to open position and said armature into position to be held by said electromagnet.

9. In a system of the class described wherein there is a main burner, a pilot burner, fuel supply means for the main burner and said pilot burner, controlling means comprising a pair of .main burner valves operative tocontrol the fuel supply for the main burner, and a pilot burner valve for controlling the fuel supply for the pilot burner, the combination with said system of a thermocouple subject to the heat of the'pilot burner, an armature connected to one of the main burner valves, an electromagnet connected to said thermocouple and cooperable with said armature to hold the main burner valve connected to said armature open by energization of the electromagnet by the thermo-electric current set up by said thermocouple when the pilot burner is ignited, thermostatic means for controlling the other of said main burner valves, means for moving the main burner valve connected to said armature and said pilot burner valve to closed position upon extinguishment of said pilot burner, selecting means for setting said controlling means for maintaining different temperatures and resetting means actuated by a portion of said selecting means and common .to the main burner valve connected to said armature and to said pilot burner valve for moving both of said valves to open position and said armature into positionto be held by said electromagnet.

10. In combination, a main burner, a pilot burner, fuel supply means for the main burner and said pilot burner, a unitary control device between said fuel supply means and said burners, a pair of main burner valves constituting a unitary part of'said control device, each operative to control the fuel supply for the main burner, a pilot burner valve constituting a unitary part of said control device for controlling the fuel supply for the pilot burner, an armature connected to one of the main burner valves, a thermocouple subject to the heat of the pilot burner, an electromagnet constituting aunitary part of said control device, said electromagnet being cooperable with said armature to hold one of said main burner valves open by energization of the electromagnet by the thermocouple when. the pilot burner is ignited, thermostatically controlled means constituting a unitary part of said control device for controlling the other of said main burner valves, means for moving the main burner valve connected to said armature and said pilot burner valve to closed position upon extinguishment of said pilot burner, selecting means for setting said control device for maintaining different temperatures, and resetting means actuated by a portion of said selecting means and common to the main burner valve connected to said armature and to said pilot burner valve for moving both of said valves to open position and said armature into position to be held by said electromagnet.

11. Safety device for heating and other apparatus comprising, in combination, means to control the supply of operative energy to the apparatus, heat generating means, pilot means for said heat generating means. a thermocouple subject to the heat of said pilot means, an electromagnet connected in circuit with said thermocouple, an armature for said electromagnet which when attracted causes said controlling means to supply operative energy to the apparatus and when retracted causes said controlling means to shut off the supply of operative energy to the apparatus, selecting means for setting said controlling means for different temperatures, and means actuated by a portion of said selecting means for resetting said armature to attracted position.

12. Safety device for heating and other apparatus comprising, in combination, heat generating means, pilot means for said heat generating means, a thermocouple subject to the heat of said pilot means, an electromagnet connected in circuit with said thermocouple, an armature for said electromagnet, controlling means including a valve member connected to said armature and held in position to permit a ed, selecting means for setting said controlling means for maintaining different temperatures, and means actuated by a portion of said selecting means for resetting said armature to attracted position and said valve member to position permitting a supply of operative energy to the apparatus.

13. Safety device for heating and other apparatus comprising, in combination, heat generating means, pilot means for said heat generating means, a thermocouple subject to the heat of said pilot vmeans, an electromagnet connected in circuit with said thermocouple, an armature for said electromagnet, controlling means including a valve member connected to said armature and held in position to permit a supply of operative energy to the apparatus when the armature is attracted and compelledto position shutting off the supply of operative energy to the apparatus when the armature is retracted, selecting means having different operations and adapted by one operation for setting said controlling means for maintaining different temperatures, and means actuated by adiiferent operation of said select- .ing means for resetting said armature to atto the apparatus.

14. Safety device for heating and other apparatus comprising, in combination, heat generating means, pilot means for said heat generating means, a thermocouple subject to the heat of said pilot means, an electromagnet connected in circuit with said thermocouple, an'armature for said electromagnet, controlling means including a valve member connected to said armature and held in position to permit a supply of operative energy to the apparatus when the armature is attracted and compelled to position shutting off the supply of operative energy to the apparatus when the armature is retracted, selecting means mounted for rotation for setting said controlling means for maintaining different temperatures, said selecting means being capable of axial movement, and means actuated by axial movement of said selecting means for resetting said armature to attracted position and said valve member to position permitting a supply of operative energy to the apparatus.

15. Safety device for heating and other apparatus comprising, in combination, heat generating means, pilot means for said heat generating means, a thermocouple subject to the heat of said pilot means, an electromagnet connected in circuit with said thermocouple, an armature for said electromagnet, controlling means including a valve member connected to said armature and heldin positionto permit a supply of operative energy to the apparatus when the armature is attracted and compelled to position shutting off the supply of operative energy to the apparatus when the armature is retracted, fluid pressure means for setting said controlling means for maintaining different temperatures, and means actuated by said fluid pressure means for resetting said armature to, attracted position and said valve member to position permitting a supply of operative energy to the apparatus.

16. A combined main burner and pilot burner control unit comprising separate fuel supply passages extending therethrough for each burner, coaxially mounted valves in said passages, a thermocouple subject to the heat of said pilot burner, an electromagnet connected in circuit with said thermocouple, an armature for said electromagnet which, when attracted, holds the valve for the main burner passage open, means for yieldingly holding the valve for the pilot burner passage open independently of said armature, and means for moving both of said valves to closed position when said armature is released and moves to its retracted position.

17. Safety device for heating and other apparatus comprising, in combination, means to control the supply of operative energy to the apparatus, an electromagnet, a thermocouple electrically connected with said electromagnet and adapted to be subjected to the-heat of a flame, an armature for said electromagnet which, when attracted, causes said controlling means to supply operative energy to the apparatus and when retracted causes said controlling means to shut off the supply of operative energy to the apparatus, selecting means for setting said controlling means for diflerent temperatures and comprising a member operable as a part of said selecting means in the selecting operation, and means actuated by said selecting member for resetting said armature to attracted position.

18. Safety device for heating and other apparatus comprising, in combination, means to control the supply of operative energy to the apparatus, an electromagnet, a thermocouple electrically connected with said electromagnet and adapted to be subjected to the heat of a flame, an armature for said electromagnet which, when attracted, causes said controlling means to supply operative energy to the apparatus and when retracted causes said controllin! means to shut 011 the supply of operative energy to the apparatus, selecting means, means for resetting said armature, and a member common to said selecting means and said resetting means for actuating said selecting means to set said controlling means for different temperatures and also adapted for actuating said resetting means to reset said armature to attracted position.

19. Safety device for heating and other apparatus comprising, in combination, heat generating means, pilot means for said heat generating means, a thermocouple subject to the heat of said pilot means, an electromagnet connected in circuit with said thermocouple, an armature for said electromagnet, controlling means including a valve member connected .to said armature and held in position to permit a supply of operative energy to the apparatus when the armature is attracted and compelled to position shutting off the supply of operative energy to the apparatus when the armature is retracted, selecting means, means for resetting said armature, and a member common to said selecting means and said resetting means for actuating said selecting means to set said controlling means for different temperatures, and also adapted for actuating said resetting means to reset said armature to attracted position.

20. In combination, a main burner, a fuel supply line leading to said burner, a pilot burner, a thermostatic valve for regulating the supply of fuel to said main burner, thermostat means for adjusting said valve to maintain selected temperatures, safety shutoff valve means for shutting off the supply of fuel to both the main burner and the pilot burner, means subject to the heat of the pilot burner for maintaining said safety shutoff valve means in open position as long as the pilot burner is lighted and operable to release said safety shutoff valve means for movement to closed-position on extinguishment of the pilot burner, temperature selecting means for adjusting said thermostatic valve to diiferent positions to select difierent temperatures to be' maintained by said thermostat means, resetting means for said safety shutoff valve means, and a member under the control of said temperature selecting means and operable as a part of said resetting means for resetting said shutoff valve means toopen position.

21. In combination, a main burner, a fuel supply line leading to said burner, a pilot burner, a thermostatic valve for regulating the supply of fuel to said main burner, thermostat means for adjusting said valve to maintain selected temperatures, safety shutoff valve means for shutting off the supply of fuel to both the main burner and the pilot burner, an electromagnet having an armature, which when attracted holds said shutoff valve open, a thermocouple placed in position to be heated by said pilot burner and connected in circuit with said electromagnet whereby said armature is held in attracted position and said safety shutoff valve means is held in open position as long as said thermocouple is heated by said pilot burner but on extinguishment of said pilot burner said armature is released for movement of the armature to retracted position and movement of said safety shutoff valve means to closed position, selecting means for adjusting said thermostatic valve to different positions to select different temperatures to be maintained by said thermostat means, resetting means for said armature and said shutoff valve means, and a member under the control of said temperature selecting means and operable as a part of said resetting means for resetting said armature to attracted position and said shutoff valve to open position.

THEODORE A. 

